The Office of the United Nations High Commissioner for Human Rights said that it would “raise these new developments with the UAE.”
Human Rights Watch has called for proof of life of the daughter of Dubai's ruler and international pressure to free her after footage emerged that appeared to show the royal in distress.
Sheikha Latifa, 35, has not been seen in public since she attempted to escape the emirate by sea in 2018, and said in a video aired by the BBC on Tuesday that she fears for her life.
Friends say they are concerned for Sheikha Latifa's safety because she hasn’t been heard from since she stopped responding to text messages six months ago.
The 35-year-old princess is the daughter of Sheikh Mohammed bin Rashid Al Maktoum, the hereditary ruler of Dubai who also serves as prime minister and vice president of the United Arab Emirates.
Prime Minister Boris Johnson later told British media he was "concerned" by the videos, while rights group Amnesty International called the footage "chilling".
"We are hopeful to see that there is movement and that there are comments being made," HRW Gulf researcher Hiba Zayadin said late on Wednesday.
"We just hope that they are followed by actions, that the UN fully and clearly calls for her release, not just proof of life.
"(Also) that she is allowed to travel abroad where she can speak freely and where she can say and speak of what she has been going through."
Sheikh Mohammed and the Dubai royal court have said Latifa is safe in the loving care of her family.
The UAE foreign ministry and Dubai Media Office have yet to comment on the case.
Calls for international action
British Foreign Secretary Dominic Raab called the videos “very distressing” and said he supported a UN investigation.
Raab said Britain was “concerned,” but he suggested there was little the government could do because Latifa is not a UK national.
The case is also particularly sensitive in Britain because of economic and historic links to Dubai and the UAE, which has built hotels and resorts to diversify an economy once based on exploiting the Emirates' energy reserves.
Sheikh Mohammed is the founder of the successful Godolphin horse-racing stable and is on friendly terms with Britain’s Queen Elizabeth II.
Supporters of an Emirati princess also urged Joe Biden to put pressure on her father to release the woman, saying the US president is one of the few world leaders with the stature to win her freedom.
David Haigh, a long-time human rights advocate in Dubai and a supporter of Sheikha Latifa, said the princess' backers were encouraged by Saudi Arabia's recent decision to release Loujain al-Hathloul, a women's rights activist who had been held for three years on charges supporters said were politically motivated.
Her release came after the Biden administration, which said it will emphasise human rights in its foreign policy, froze some arms sales to Saudi Arabia.
“The only level of people who are going to have enough influence to effectively force Latifa's father to open her jail are people like Joe Biden, and there’s very few of them,” Haigh said. “And he’s also shown that he can do it with Saudi.”
'Pleas for help'
"We are extremely concerned for her safety, as friends say all contact with her stopped in recent months," said Lynn Maalouf, Amnesty's deputy director for the Middle East and North Africa.
"Sheikha Latifa may be detained in a 'golden cage', but that does not change the fact that her deprivation of liberty is arbitrary," she added in a statement on Thursday.
"Given its prolonged nature would amount to torture, Amnesty International calls on the international community to turn its attention to Sheikha Latifa's pleas for help."
The BBC said the clips were filmed roughly a year after she was captured and returned to Dubai, showing her crouched in a corner of what she says is a bathroom.
"I'm a hostage and this villa has been converted into a jail," she says in one cellphone video.
"There's five policemen outside and two policewomen inside the house. Every day I am worried about my safety and my life."
In another video, Latifa says her situation is "getting more desperate every day".
"I don't want to be a hostage in this jail villa. I just want to be free," she says.
The Office of the United Nations High Commissioner for Human Rights will "certainly raise these new developments with the UAE", a spokesperson told the BBC.